When the makers of the distinctive Swiss confection Toblerone reconfigured their triangular treat last year to slim down its hallmark summits and widen the valleys between them, a potential rival — Britain’s Poundland discount chain — saw a niche in the market.

What Poundland perhaps did not anticipate was the battle of the brands that kept its new offering off the shelves while the owners of Toblerone, the giant American conglomerate Mondelez International, challenged the British company’s right to make a candy bar that looked so similar. Only in October did a three-month bout of legal arm-wrestling draw to an end. And only this week did Poundland’s bars hit the shelves — though not quite in the way the British chain had intended, and not, in their current shape at least, for long.

So what was all the fuss about?

Like Toblerone, Poundland’s version has peaks and troughs. It, too, originally came swathed in a golden wrapper with red lettering. But while the classic Toblerone bars had become lighter in weight in the reconfiguring — though their price remained the same — Poundland’s bar would be chunkier and cheaper, at one pound, or about $1.35, each.

Not, of course, that this was some crude copycat. If, as some contend, Toblerone was modeled on the soaring pyramid of a mountain — the Matterhorn on the Italian-Swiss border, which is about 14,690 feet high — Poundland’s bar was said to have been inspired by two less vertiginous hills in the English county of Shropshire near the border with Wales — the Ercall, at 460 feet, and the Wrekin, at 1,335 feet.

Hence the shape of the Poundland bar, with a double set of summits between each valley.

And hence its name: Twin Peaks, with what Poundland called “a distinctive British flavor compared to Toblerone’s Swiss chocolate nougat.”

Not only that, Poundland asserted, Toblerone had lost its right to exclusivity since it had ceased to be distinctive enough to claim a valid trademark.

Mondelez hit back: Toblerone, it said, was “one of the most loved, unique, best-value Swiss-made chocolate products in the world. Its high quality special Swiss recipe and triangular peaks have been delighting people around the world since 1908, and we believe will continue to do so for future generations of chocolate lovers too.”

Nonetheless, there was some compromise.

Poundland, part of the multinational retailer Steinhoff International, had delayed introducing the bar in July. But, after negotiations with Mondelez, it was permitted to begin selling in its nearly 900 stores on Monday the 500,000 bars already in production — provided it changed the background color of their wrappers from gold to blue. And the lettering was changed: to gold, from the original red.

Once the initial 500,000 bars have been sold, Poundland said in a news release, it will “revise the shape” so that the bar “better represents the outline of the Wrekin and Ercall hills.”

A version of this article appears in print on , on Page A4 of the New York edition with the headline: Toblerone vs. Poundland: A Chocolate Food Fight. Order Reprints | Today’s Paper | Subscribe